The invention relates to a method for operating a vehicle and to a device for carrying out the method.
The method according to the invention is based on a method in which access authorization is determined in a dialogue between a control device, which is fixed in the vehicle, and an authorization verification device (BNE), which is carried by the user. The authorization verification device (BNE) is also used for enabling the vehicle drive unit to start.
A method of this type is known from German Patent Document DE 36 15 890 A. In that document, the dialogue between the control device and the authorization verification device (BNE) is carried out in a wireless manner. The authorization verification device is, for example, a transponder which receives an interrogation signal emitted by the control device and emits a response signal with a response code. If the user is authorized, the control device recognizes this user because of the correct response code and permits or implements the unlocking of the vehicles doors. In the case of the known method, it will then be easily possible to start the vehicle drive unit. A rotary button provided for this purpose is combined with the steering wheel lock and can easily be operated. The problem arises in this case that, for staring the vehicle drive unit, it is sufficient to unlock the vehicle. A vehicle passenger can therefore also start the operation of the vehicle drive unit if the authorized vehicle user carrying the BNE does not want him to do so.
The described problem becomes particularly serious when the access authorization is queried in a form known from German Patent Document DE 195 16 316 A. There, the question-answer dialogue is already carried out when the authorized user approaches the door handle with his hand. If he does this, for example, not with the intention of opening the vehicle door and does not recognize that the dialogue has nevertheless resulted in his identification and the vehicle is unlocked, it will then be possible for a third party to enter the vehicle and start the drive unit without the authorized user's knowledge.
In addition to the known method, it will in the future also be possible to verify the access authorization by individual body-related characteristics. An identification is known, for example, which takes place by means of finger [print or a] prints or speech recognition. Also, in the case of such a physiological authorization verification device, in the quasi automatic clearing of the vehicle drive unit known from German Patent Document DE 36 15 890 A, there is the problem of an undesired or unauthorized start of the operation of this unit.
It is an object of the invention to provide a method of the above-mentioned type in which this problem is eliminated.
The invention achieves this object by a method for operating a vehicle, in which the access authorization is determined in a dialogue between a control device, which is fixed in the vehicle, and an authorization verification device (BNE), which is carried by the user. The authorization verification device (BNE) is also used for enabling the vehicle drive unit to start. The authorization verification device (BNE) is interrogated for the purpose of starting the vehicle drive unit independently of the process for establishing access authorization.
Because the authorization to start the operation of the vehicle drive unit is now no longer coupled to a mechanical ignition key, the problem of a loss of the memory during the operation of the vehicle drive unit occurs particularly when an electronic memory is provided for the access authorization verification. This loss may be unnoticed by the authorized user; for example, the memory may be removed unnoticed from the vehicle.
The same problem occurs when the memory loses its capacity to transmit the access authorization code. For example, in the event of an electrical defect of the BNE, which occurs during the operation of the vehicle drive unit, the BNE becomes ineffective and no longer permits the subsequent start of the operation of the vehicle drive unit. This takes place, for example, if the drive unit is constructed as an internal-combustion engine, and the engine is stopped for a short time in front of a closed grade crossing.
Because the access code must be transmitted for starting the vehicle drive unit, this results in a considerable problem for the vehicle user. In order to avoid this problem, the query of the access code can also take place during and/or after the conclusion of the operation of the vehicle drive unit. The query during the operation makes it possible to rapidly detect the loss. The prerequisite is only a corresponding frequency of the query.
The query after the conclusion of the operation permits at least the taking of appropriate measures in order to then be able to start the vehicle again. The result of the query of the access code during or after the conclusion of the operation of the vehicle drive unit may be the emission of a warning signal.
With respect to the above, it is advantageous to provide in this case a vehicle-fixed memory for the access code which will then be unlocked and can, for example, also be removed from the vehicle by the user.
This memory is provided in addition to the actual memory for the access code. This redundant memory will then be operative. It may be constructed as a mechanical part which is inserted in the authorization verification device and functionally replaces the memory for the access code provided there which may be defective. The memory can then be inserted alone or together with the BNE in an activating part for the start of the operation or the operation of the vehicle drive unit. It can also be connected with a mechanical key which is then placed in an ignition lock and permits the start of the operation of the vehicle drive unit in the conventional manner.
In order to indicate to the vehicle user that the redundant memory has become effective, the vehicle user can be conspicuously informed of the implemented unlocking of the vehicle-fixed memory. This clearly reduces the danger of an accidental leaving of the redundant memory in the vehicle and the related possibility of a start of the vehicle by the unauthorized user.
If, in the process, the memory is ejected out of its receiving device, this special situation is not only clearly pointed out to the vehicle user but is also caused to pay special attention to the locking operation of the vehicle and to optionally carry out the locking conventionally, for example, by means of a mechanical key which, as a rule, is also present.
This eliminates the risk of enabling in an emergency by the measures provided for this purpose an unauthorized person to use the vehicle. The authorized user is caused to carry out the required measures (such as the removal of the redundant memory) himself.
The invention will be further explained by means of the drawings.